question about importing models
there is a lack of information in your question. What is the file extention? The model comes from another .blend file? 

If it comes from another blender files the process you're looking for is to append something in your project. When you import a file to your project only the 3D information will transfer (vertices, edges and meshes). If you want to insert another informations such as materials, textures, etc you need to append these informations into your own blend file.  



It is a step by step process, so I advise you to  see this video.

I hope it helps and welcome to the comunity :)